Development and miscellaneous randomness.

Third-party filament, PLA extruder, recent prints

I got another new filament cartridge (green) on 5/15 and swapped it in to try out. When the first print started with this new cartridge, I got a 010 error on the printer. According to the XYZ error list from the user manual, that means “Extruder temperature too high or too low”, which is a little scary. Hopefully the temperature is too low and not too high. I restarted the printer, tried the print again, and it worked fine. This is a little disconcerting to me, since it’s the second recent error that was fixed by basically restarting. I got this same error again on 5/29 and restarting fixed it again. I’m not sure what was going on, but hopefully it won’t be an issue anymore due to the other things I’ve done to the printer since then (more below).

I also decided to try some third-party ABS filament with the printer. A coworker recommended Hatchbox (though, he’s been using PLA, so wasn’t certain of the ABS quality), so I bought a spool of silver Hatchbox ABS from Amazon (http://smile.amazon.com/HATCHBOX-1-75mm-3D-Printer-Filament/dp/B00M0CS1BQ/ref=sr_1_20?s=industrial&ie=UTF8&qid=1435772080&sr=1-20). Third party filament is cheaper than the printer company’s, but that was not my primary concern. My main driver is that the printer company’s color options are EXTREMELY limited. The printer company does not make this easy, since the printer reads from a chip on their filament cartridges and will not print if their cartridge is not present (or doesn’t have some filament remaining on their counter). There are ways to work around this. The basic idea is that you leave one of their cartridges in, but feed the third-party filament into the extruder instead of the filament from the cartridge. Since the filament remaining counter will be decrementing on the cartridge, it’s also necessary to reset that counter periodically. That is pretty easy to do using an Arduino using the sketch from here (https://github.com/voltivo/davinci_filament_reset_arduino/blob/master/xyz_dv_eprom.ino). I printed the chip holder from Thingiverse to help with this (http://www.thingiverse.com/thing:502510). I am also working on a more robust sketch that will allow entering the values when running it (versus their being hard-coded), but it’s not quite ready yet.

My confidence in the third-party filament waned pretty quickly. This filament is very brittle and repeatedly broke while I was trying to get it setup on a spool holder and feed it into the printer. I did a test print and ran into major issues – the extruder clicked constantly and the print was extremely poor quality. My suspicion was that the extruder was having issues pulling the filament in from the spool holder on the back, so I found a spool holder that I could put on top of the printer (http://www.thingiverse.com/thing:438174) and printed it with my green filament. My thought here was that gravity could help with the feeding of the filament and it did seem to help when I tested again. The clicking was gone! However, there was still an issue during the print. I wasn’t watching it, so I’m not sure what went wrong. I know… shame on me.

Time for a new theory: My A/C vent is above the printer, so maybe it’s cooling the filament (which, for third-party filament, is outside the printer) so much that it doesn’t melt properly in the extruder. I had also been using a floor fan to blow the ABS fumes out a window and that has probably been compounding the cooling of the external filament. So, I repointed the ceiling vent and moved the fan. The next print turned out acceptably, but still not as good as the first-party filament. I’ll do more experimentation later.

I also finished the design for the final piece of my ventilation/exhaust system. I’ve put the model up on Thingiverse (http://www.thingiverse.com/thing:875264). I printed it, hooked it all up, and it works great. There is no ABS fume smell at all anymore while I’m printing.

Timelapse of printing the ventilation piece:

About two weeks ago, I decided to go ahead and buy the extruder from XYZ that can print using PLA as well. It arrived last week and I went through the steps to swap out the extruder on 6/24. I initially had some issues with ABS no longer sticking to the build plate and the extruder not cooling down when it wasn’t printing. The tool to update XYZware (so it could print PLA) repeatedly failed to work, so I decided to go ahead and update my XYZware and printer firmware. I hope this won’t break my use of third-party filament, but I haven’t checked yet. After that, the extruder upgrade tool worked, XYZware is okay with printing PLA, and the extruder is cooling down properly. ABS still seems to be having some sticking issues, but I’m sure I’ll get that worked out.

As far as PLA prints, I’ve done a couple test prints successfully so far. I printed a hollow test box and a star vase, both of which turned out well.

Part of swapping out the extruder was calibrating the printer bed, which I had not gone through before. It’s a pretty painful process, but there’s a website tool that helped me a bit: http://ddd.stefanomenci.com. Basically, you choose to calibrate on the printer, it measures three points on the print bed, and shows you the three measurement numbers. You then try to figure out what adjustments need to be made to three screws beneath the bed in order to get the three measurements as close to one another as possible. Once you make some adjustments, you run calibrate again, it measures, and shows the three measurement numbers again. Rinse and repeat until the numbers are close enough for the calibration to report success. This is a bit of guesswork and it’s pretty frustrating. But I did it!

I took some photos of the extruder module and the filament feeder while I had the module disconnected. You can see the feeding wheels and how the filament feeds into the hot end. One of the feeding wheels has black stripes on it that seem like they could be used to identify filament jams, but I don’t believe the printer actually does that (it hasn’t informed me when I’ve had filament stop flowing during prints, anyway).

One more comment about the extruder swap: XYZ’s site says to use a different extruder for each type of material. This does not seem right to me and I certainly hope it’s not a necessity. Swapping the extruder and calibrating every time I switch filament type is just not practical.

Recent prints not related to above (before extruder swap):

I printed a sign to go on the dishwasher that indicates whether the dishes inside are clean or dirty.

I designed a little bit that can allow using an electric screwdriver or drill with my manual burr coffee grinder.

My son wanted a small toy alien, so I printed a Marvin keychain for him. To get decent quality, I had to print 2 of them at the same time along with a hollow box to slow down the printing. That allows the smaller pieces to cool a bit before the hot end runs over them again for the next layers.